<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<style>
    header{
        background-color: pink;
        line-height: 50px;
        height: 50px;
    }
    main{
        background-color: yellow;
        line-height: 600px;
        height: 600px;
    }
    footer{
        background-color: green;
        line-height: 50px;
        height: 50px;
    }
    .content{
        max-width: 1000px;
        margin: 0 auto;
    }
</style>
<body>
    <header>
        <div class="content" style="background-color: black;"></div>
    </header>
    <main  class="content">

    </main>
    <footer>
        <div class="content"></div>
    </footer>
</body>
</html>